X-Git-Url: http://git.osdn.net/view?a=blobdiff_plain;f=ipc%2Fshm.c;h=06e5cf2fe019faee43aa9f8ca9f17cad4973b74d;hb=e9d92d223381f1f3be5d87322b576721d3b93612;hp=6d767071c3673dce09984933c3a444d78880bd10;hpb=bbe179f88d39274630823a0dc07d2714fd19a103;p=uclinux-h8%2Flinux.git

diff --git a/ipc/shm.c b/ipc/shm.c
index 6d767071c367..06e5cf2fe019 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -129,7 +129,7 @@ void __init shm_init(void)
 
 static inline struct shmid_kernel *shm_obtain_object(struct ipc_namespace *ns, int id)
 {
-	struct kern_ipc_perm *ipcp = ipc_obtain_object(&shm_ids(ns), id);
+	struct kern_ipc_perm *ipcp = ipc_obtain_object_idr(&shm_ids(ns), id);
 
 	if (IS_ERR(ipcp))
 		return ERR_CAST(ipcp);
@@ -155,8 +155,11 @@ static inline struct shmid_kernel *shm_lock(struct ipc_namespace *ns, int id)
 {
 	struct kern_ipc_perm *ipcp = ipc_lock(&shm_ids(ns), id);
 
-	if (IS_ERR(ipcp))
-		return (struct shmid_kernel *)ipcp;
+	/*
+	 * We raced in the idr lookup or with shm_destroy().  Either way, the
+	 * ID is busted.
+	 */
+	BUG_ON(IS_ERR(ipcp));
 
 	return container_of(ipcp, struct shmid_kernel, shm_perm);
 }
@@ -191,7 +194,6 @@ static void shm_open(struct vm_area_struct *vma)
 	struct shmid_kernel *shp;
 
 	shp = shm_lock(sfd->ns, sfd->id);
-	BUG_ON(IS_ERR(shp));
 	shp->shm_atim = get_seconds();
 	shp->shm_lprid = task_tgid_vnr(current);
 	shp->shm_nattch++;
@@ -258,7 +260,6 @@ static void shm_close(struct vm_area_struct *vma)
 	down_write(&shm_ids(ns).rwsem);
 	/* remove from the list of attaches of the shm segment */
 	shp = shm_lock(ns, sfd->id);
-	BUG_ON(IS_ERR(shp));
 	shp->shm_lprid = task_tgid_vnr(current);
 	shp->shm_dtim = get_seconds();
 	shp->shm_nattch--;
@@ -1191,7 +1192,6 @@ out_fput:
 out_nattch:
 	down_write(&shm_ids(ns).rwsem);
 	shp = shm_lock(ns, shmid);
-	BUG_ON(IS_ERR(shp));
 	shp->shm_nattch--;
 	if (shm_may_destroy(ns, shp))
 		shm_destroy(ns, shp);